flake: add store_path

flake.nix

@@ -28,6 +28,12 @@
               description = "Enable video playback";
             };
 
+            store_path = lib.mkOption {
+              type = lib.types.str;
+              default = "/var/tmp/queuecube";
+              description = "Path to the store for QueueCube";
+            };
+
             invidious = lib.mkOption {
               type = lib.types.submodule {
                 options = {
@@ -81,6 +87,7 @@
                 ENABLE_VIDEO = if cfg.enable_video then "1" else "0";
                 USE_INVIDIOUS = if cfg.invidious.enable then "1" else "0";
                 INVIDIOUS_URL = cfg.invidious.url;
+                STORE_PATH = cfg.store_path;
               };
             };
           };